To characterize the signal-processing performance of the human visual system in the spatial, temporal, and chromatic domains, we have been using both Maxwellian view and CRT display techniques for measuring the visual sensitivity to steady, moving, and flickering gratings and to homochromatic and heterochromatic flickering fields, with and without retinal image stabilization. New facilities, nearing completion, will extend our capabilities from one-dimensional to two-dimensional stabilization and from hardware signal generators to software generation of arbitrary spatio-chromatic stimuli. Essential to this effort is the acquisition of a new, greatly improved eyetracker. Since we can simulate the effects of eye movements on the visibility of gratings by stabilizing the retinal image and moving the object at a slow, constant velocity, we propose to conduct many of our pattern-vision studies with this type of artificial eye-movement, thus eliminating an important artifact. Having demonstrated that the contrast sensitivity curve can be turned to any desired spatial frequency by changing the velocity of the (stabilized) stimulus, we will continue to explore the relation between pattern adaptation and velocity tuning. We will also continue to search for two-dimensional patterns (e.g., crossed gratings, circular Bessel functions) that demonstrate so-called Fourier effects without pattern adaptation. We propose to study the chromatic analogs of many of these luminous-contrast effects: e.g., does the circular-target effect or the velocity-tuning effect occur with purely chromatic gratings? Having discovered the existence of "forbidden cones" in dichromats, we propose to study their spatial arrangement by the silent-mechanism technique and compare the results to similar data from normal trichromats. A new effort will be the exploration of retinal inhomogeneity by several methods, including our newly devised, stabilized-window technique. Our theoretical studies of the mechanisms underlying the spatio-temporal threshold surface look very promising and will be pursued vigorously.